Split platen



Sept. 26, 1939. 1 Q SHERMAN ET AL y2,173,864

SPLIT PLATEN Filed Nov. 29, 19,35

Patented Sept.v 26, 1939` UNITED STATES PATENT OFFICE ,SPLIT PLATEN John Q. Sherman and Albert W. Metzner, Dayton, Ohio; said Metzner assignor to said Sherman Application November 29, 1935, Serial No. 52,169

7 Claims. (Cl.197-144) This invention relates to platen rolls for writ- A further and important object of the invening machines and more particularly to the contion is to facilitate the commercial manufacture struction and method of manufacture of removaof sectional platen rolls herein described.

bly mounted rolls which are interchangeable With the above primary and other incidental with other like platen rolls of different lengths objects in View, as will more fully appear in the 5 or of different surface characteristics for use specification, the invention consists of the feaon typewriters, tabulating and computing matures of construction, the parts and combinations chines and analogous mechanisms to accommothereof, and the mode ofv operation, or their date stationery of different widths or different equivalents, as hereinafter described and set 10 surface characteristics or materials. forth in the claims. l0

The commercial production of such inter- Referring to the accompanying drawing changeable platen rolls presents some diihcult wherein is shown the preferred but obviously not manufacturing problems which are solved by the necessarily the only form of embodiment of the structural features and method f manufacture invention, Fig. l is a side elevation o f the platen forming the subject matter hereof. Aroll assembly forming the subject matter hereof. 15

While for illustrative purposes the present Fig. 2 is a transverse sectional view on line platen roll is shown in association with pin 2 2 of Fig. 1. wheel feeding devices engageable in marginally Fig. 3 is a transverse sectional perspective punched holes in the writing material, it is to be -view of one or the platen roll sections at a midunderstood that it may also be employed in assolength point. l 20 ciation with other suitable mounting heads de- Fig- 4 is a perspective, end elevation of one of void of feeding pins for use with frictional feedthe platen roll sections. ing means of a writing machine. Fig. 5 is an enlarged detail sectional view.

As herein shown and described the present Like parts are indicated by similar characters platen roll is longitudinally split to facilitate of reference throughout the several views,`

its installation and removal from between the Referring to the drawing, I is the shaft of a axially adjustable pin wheel units or mounting platen roll to be mounted in suitable bearings in heads thereby enabling a succession of such a writing machine carriage or in the frame of a platen rolls of different lengths or of vdifferent computing or tabulating machine upon which surface characteristics or degree of hardness to are carried a pair of axially adjustable mounting 30 be employed interchangeably with the same pin heads 2 and 3. For illustrative purposes these wheel units or mounting heads. mounting heads 2 and 3 in the present instance This application is a continuation in part of are shown as pin wheel units for feeding engagecopending application, Serial Number 687,303, ment with marginally punched holes in record ,35 filed August29, 1933, now matured into Letters material. It is to be understood however that Patent No. 2,067,211, of January 12, 1937, and the pin wheel feedfeature is not essential to the cross reference is made to co-pending applicapresent invention and that the feeding pins may tion Serial No. 68,219, filed March` 11, 1936. be omitted from the mounting heads. 'I'he The object of the invention is to improve the mounting heads 2 and 3 are splined upon the 40 construction as well as the means and mode of shaft I for unison rotation therewith. The 40 production of interchangeable platen rolls mounting head 2 is formed with an inwardly whereby they may not only be economically projectinghub 4 in which is mounted a radially manufactured but will be more eilicient in use, disposed spline or key 5. The spline 5 is fixedly of increased durability, greaterV accuracy, and secured in the hub 4 with its inner end projectuniform character, easily intel-changed and uning interiorly thereof into engagement with a i5 likely to get out of repair. longitudinal key Way or groove in the shaft l to "An important object of the inventionis to afford positive rotative driving lengagement provide an improved method of securing the therewith, and its outer end projects beyond the rubber or other surfacing material upon the core periphery of the hub 4 into driving engagement portions of the platen roll sections to prevent with a slot intermediate the platen roll sections 50 accidental stripping or loosening while in use. to afford a rotative driving engagement between A further object of the invention is to provide the roll sections and the mounting head. The an improved method of production .whereby uniengagement of the inner end of the key wayor formity of manufacture, accuracy of parts, and spline 5 within vthe longitudinal slot 6 of the interchangealoilityv of sections is assured. shaft I permits axial adjustment of the mounting head 2 upon thershaft while maintaining its driving engagement therewith in all positions of such adjustment. In order to secure the mounting head 2 in any one of several positions of axial adjustment the hubl 4 is provided with a transverse slot in which is pivotally mounted a segment shaped key or latch 8 engageable in any one of a series of notches 9 in the periphery of the shaft I under influence of a spring I0 seated in a bore in the hub 4.

By lifting the latch 8 against the tension of the spring I0 as shown by dotted lines in Fig. 2 the mounting head 2 is released from the shaft for sliding adjustment thereon to different position in which it is again held by the engagement of the latch 8 in the corresponding notch 9. The inner face of the mounting head 2 is provided with an angular or V-shaped rib I I in concentric spaced relation with the hub 4 for engagement in corresponding grooves in the extremities of the platen roll sections to be described.

The opposite mounting head 3 is of the same general character having a corresponding inwardly projecting hub 4 having a key or spline also engaging in the longitudinal slot '6 of the shaft I to afford driving engagement. The mounting head 3 is also provided with the concentric angular rib II for interlocking engagement with the platenroll section but does not have the splined rotative driving connection therewith. The mounting head 3 is not locked in definite position upon the shaft I but is free for sliding `movement thereon relative to the opposite mounting head 2. It is held in its position of adjustment by a thrust collar or disc I3 screwthreaded upon the extremity I2 of the shaft I and bearing against the outer side of the mounting head.

LIhe platen roll comprises two longitudinally separable semi-cylindrical sections I5.which are interposed between and engaged by the respective mounting heads 2 and 3. The platen roll sections I5 comprise an inner core or rigid support I6 which preferably although not necessarily is initially a length of metal tubing severed longitudinally and the severed edges reduced sufliciently to accommodate the overlapping portions of the outer or cover stratum of rubber or the like. The platen roll is not divided exactly upon its diametrical plane. In order to offset the longitudinal joint of the platen-roll relative to the feeding pins and especially to avoid possible registry of the platen roll joints with the writing lines as the joints or lines of severance of the platen roll pass the writing position, one platen roll section is slightly larger than the other. For illustrative purposes, but without intent of limiting the invention to any specific dimension, in practice one section of a standard size of platen roll is 1%3 of its circumferential dimension while the other section is 1%3 thereof. Being of such slightly different size the two portionsof the roll have the appearance of being equal size. and halves of the cylinder, in which case the joint or line of severance of the sections would coincide with writing lines as the platen roll is rotated. Not only is the division of the cylindrical roll at variance with the diametrical plane but the adjacent marginal faces I8 of the core portion I6 are preferably beveled or inclined inwardly slightly in divergent relation with their radial planes as isshown more clearly in the enlarged detail view Fig. 5.

The opposite ends of the internal core or sup- `relieved or cut away porting members I6 are provided with concentric angular grooves I9 which conform to and receive the concentric ribs II. of the respective mounting heads 2 and 3 when the platen roll is assembled therebetween. Likewise the adjacent marginal faces of the respective core portions I6 are as at 20 in Fig. 3 to afford therebetween a slot to receive the outer end of the key or spline 5 when the platen roll sections I5 are assembled one upon the other.

Fixedly secured about the outer convex surfaces of the semi-cylindrical cores I6 preferably by being vulcanized thereto are the cover strata I1 of rubber or the like which cover strata are continued at the opposite edges of the core member I6 into overlapping relation with the inwardly beveled marginal surfaces I8 thereof. In this manner the resilient cover portion I1 is clenched over the edge of the core and interlocked therewith so that the danger of accidental loosening or stripping offtheresilient surfacing'material I1 from the core I6 is minimized. This is especially true when the complementary sections of the platen roll are engaged one with the other in abutting relation and so held between the mounting heads 2 and 3in which case the overlapping marginal extensions 2| of the resilient coverstrata I1 are clamped between the respective core portions I6.

In the manufacture of the sectional platen roll elements I5 the outer faces of the core portion IBlare preferably although not necessarily etched, roughened or otherwise treated to facilitate adhesion of the overlying rubber surface strata I1. The resilient cover I1 of rubber or the like is then molded and vulcanized about the convex face of the core portion I6 and in overlapping relation with the marginal faces I8 thereof as at 2 I. After being vulcanized the overlapping marginal extensions 2I of the sections are accurately ground or otherwise finished to afford uniform smooth surfaces coincident with the radial plane of the unit. As before mentioned in order to offset the juncture lines out of registry with the writing lines as the platen rotates these finished surfaces of the respective sections preferably do not line in a common plane but are slightly angular relative to each other. After the' contacting or abutting surfaces of the marginal extensions 2I have been reduced to a uniformly at smooth surfaces by grinding or otherwise the complementary sections of the platen roll are assembled in contacting relation with each other and so held while the outer cylindrical surfaces of the surfacing material I1 is reduced to a smooth finished cylindrical surface throughout by grinding or otherwise. By such method the respective sections of the roll are so accurately fitted and conformed one to the other that the juncture lines or Joints are hardly perceptible. These platen roll sections are manufactured in different lengths for use with record material of different width. The surface covering I1 may also be of different materials, or if of rubber they may be of different degrees of hardness or of difhard resistant character such as pyroxylin or Cel.

luloid or may be metal surfaced for stencil cutting purposes and the like.

It will be understood that by the present construction of platen rolls such roll sections ofdif- 'IB performed may require.

In order to interchange one pair of platen rolls for another of different size or surface characterthe angular bead H of the head 3 engages. The mounting head 3 is thereupon held in such abutting or clamping relation with the platen roll .sections by adjustment of the thrust collar or disc I2 upon the screw-threaded extremity I3 of the shaft.

In lieu of nishing the abutting surfaces of the portions 2l upon slightly angular radial planes as before mentioned for economy and convenience of manufacture the opposite margins 2| may be finished in a common flat plane which due to the slight diierence in the size of the sections will be offset slightly from the diametrical plane of the roll. This enables margins o'f the respective sections to be simultaneously finished by passing them beneath a cylindrical grinder or the like having uniform operative engagement with both margins.

From the above description it will be apparent that there is thus provided a device of the charcation in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantages.

While in order to comply with the statute, the invention has been described in language more or less specic as to structural features, it is to be understood that the invention is not limited to the specific features shown, but that the means and construction herein disclosed comprise the preferred form of several modes of putting the invention into eiect, and the invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.

Having thus described our invention, we claim:

.different length is 1. A platen roll for writing and imprinting machines wherein a removable portion thereof interchangeable ywith other similar portions of different length is when in assembled relation.

2. A platen roll for a writing machine comprising a cylindrical body longitudinally divisible into complementary sections, each section including a core member the marginal edges of which margins inturned over the beveled edges of the corresponding core member and interlocked therewith.

3. A platen roll for writing machines comprising a plurality of cylindrical segments each including a core member and an adherent cover stratum permanently aixed about the exterior the core member, margins of the covers of succeeding segmental sections being held between adjacent core members when the segments are assembled into a roll.

4. A platen roll for writing machines comprising a plurality of separable segments ofa cylin- 5. A platen roll for writing and imprinting machines wherein a removable portion thereof interchangeable with other similar portions of differlength is detachably engaged between relapermanently attached cover portion extending over the convex face of each core portion, and into overlapping relation with `the marginal faces of the core.

6. A- platen roll for writing and imprinting machines wherein a removable portion thereof interchangeable with other similar portions of detachably engaged. between V axially adjustable mounting heads characterized by a plurality of separable tion extending over the convex face of each core portion, and thence between core portions of contiguous segments.

7. As an article of manufacture, a platen roll of the concavo-convex core, and inwardly di- 

